Operating System level virtualization is hitting hard now, as much as VM’s did just a few years ago. Docker is the popular framework for this matter, the new kid on the block so to speak. This is the hot spot now and if anyone wants to appear knowledgeable about system administration knowing this technology is […]

How to install Docker on Ubuntu 18.04

Symbolic and Hard Links in UNIX and Linux
Symbolic and Hard Links are useful ways to reference to information on a disk, both found in UNIX and Linux systems. While they seem similar in the surface they are quite different in how they work and it what can be achieved when using them. If you find the articles in Adminbyaccident.com useful to you, […]

How to install sudo in FreeBSD
Sudo is a very useful application. It allows a regular user to perform tasks only reserved to the root account. There is lots of documentation about sudo and there is even a book about it called “Sudo Mastery”. If you need to investigate deep on this, buy it. Why do you need this? Well… Everyone […]

How to manage site visitors based on IP Geolocation
Whenever someone publishes a website on the internet, most of the times, their intention is that site to be seen around the globe. However, as a site administrator you may want to divert users from one country to visit some specific version of that site, maybe because of the visitor’s language. Other times, less often […]

How to test pfSense on VirtualBox running on FreeBSD
There are other guides on how to do this on Windows, Mac, but not on FreeBSD, so here goes a how to pfSense on Virtualbox running on FreeBSD. Before going to it, let’s address the first question, which is what is pfSense. pfSense is a FreeBSD based distribution made for networking purposes. The company behind […]

How to install OSSEC server on Ubuntu
OSSEC is a host-based intrusion detection system (HIDS). It is specially well known for monitoring files that shouldn’t change on a system (such as critical system files, or binaries, etc) and warning administrators (or anyone you’d like) about those issues. But it does more such as rootkit detection and log analysis with a dedicated engine. […]

How to install OpenVAS on FreeBSD
Was ist das? OpenVAS is a vulnerability scanner. If you are unfamiliar to the vulnerability scanning world this can be an overwhelmingly experience but tools like this are what makes the matter more accessible, more manageable, easy to see and easy to fix. Before digging into the matter at hand here, that is how to […]

What is GNU/Linux?
To answer this question one must split it. Plus make other questions like: «What is a, so called, Linux distro?». It seems complex and it is in a way. But let´s explain GNU/Linux in simple terms. GNU stands for GNU is Not UNIX. So it´s clear is not UNIX but it´s related to it in […]

How to connect a FreeBSD box to the internet through an Android device via an USB port
FreeBSD is known to be very suitable for computer servers, from Netflix streaming to Whatsapp messaging as powerful examples. Some also use FreeBSD as a workstation OS. I am one of those using BSD on both camps, although I also use some GNU/Linux boxes for ‘trivial’ purposes. In modern times having an internet connection seems […]

How to patch Spectre and Meltdown the ROM way
In a previous article I briefly, sort of, talked about the Spectre and Meltdown vulnerabilities. I have also written two guides to patch them from the OS side using a UNIX flavour from the BSD camp and a GNU/Linux distribution. Both actions resulted successful but there is a third way to patch this vulnerabilities. Regular […]
